In public places with a large area and complex environment, such as airport, it is difficult to accurately find and quickly reach a destination due to the various miscellaneous indicators. At present, small vehicles, such as multimedia trolleys equipped with intelligent mobile service terminals or the like, are put in public places for people to use. Theses multimedia trolleys can assist people to transport goods and quickly guide people to reach their destinations by using multimedia playing devices installed thereon, thus providing convenience to the users. It is necessary to frequently charge the battery of the mobile service terminal of a trolley due to the frequent use of the multimedia trolley. Multiple conventional multimedia trolleys are concatenated in tandem to form a series circuit of charging connectors and then pushed to a charging facility for simultaneous charging. Due to the fact that the public places are always crowded with people, it may be necessary to brake or turn suddenly when encountering obstacles such as people or luggage. When the existing multiple multimedia trolleys are pushed forward in a concatenated manner, as lacking of a stop means between a front trolley and a back trolley, a sudden brake or turn will cause the trolley to lean forward and even overturn due to an unsteady gravity center of the trolley. Even worse, this may also lead to damage of the multimedia player installed on the trolley. In addition, when the trolleys are pushed forward in a concatenated manner, how to accurately and reliably connect the charging connectors of the front and back trolleys to shorten the time for the staff to check the circuit is also a problem demanding prompt solution.